About This Solved Paper
| Prepared by | Unnati Education, IGNOU-experienced academic content team |
| Qualification | Graduates with specialization in Physical Chemistry and Organic Chemistry |
| Programme | IGNOU Bachelor of Science General (BSCG) and Bachelor of Science Multidisciplinary (BSCM) |
| Institution Reference | IGNOU Term-End Examination, December 2025 |
BCHCT-135 is one of those chemistry papers that splits right down the middle: half physical chemistry, half organic. That combination trips up a lot of BSCG and BSCM students because the preparation strategy for each part is completely different. Phase diagrams and electrochemistry need numerical accuracy. Organic reactions need mechanism clarity. Having the actual BCHCT 135 Question Paper December 2025 alongside structured solved answers helps you understand exactly what was asked and how to approach each section with confidence.
Download Now ā Get BCHCT-135 Solved Question Paper December 2025 IGNOU
The complete December 2025 question paper is right here on this page. Before you attempt anything, read through both parts fully. Choosing the right five from each section can save you a lot of time in the exam hall. Once you are ready for the solved version, the IGNOU BCHCT-135 question paper with complete answers is just a message away. Reach out via WhatsApp or the contact link on this page, share your programme and exam cycle, and we will send your solved paper within a few hours.
What Is BCHCT 135 Question Paper December 2025?
The BCHCT 135 December 2025 question paper is the official IGNOU Term-End Examination paper for Solutions, Phase Equilibrium, Conductance, Electrochemistry and Functional Group Organic Chemistry-II, under BSCG and BSCM, carrying 50 marks across ten questions.
This paper demands two very different modes of thinking in one sitting. Part A tests your grasp of physical chemistry: phase diagrams, conductance, electrode potentials, Raoult's law, and Gibbs phase rule. Part B shifts you into organic chemistry: completing reactions, understanding carbohydrate structures, protein hierarchy, and amino acid synthesis. Strong preparation means you cannot ignore either half. The BCHCT-135 December 2025 question paper rewards students who have genuinely worked through both sections.
About IGNOU BCHCT-135 ā Solutions, Phase Equilibrium, Conductance and Electrochemistry
BCHCT-135 sits within the IGNOU BSCG and BSCM chemistry curriculum as a paper that bridges thermodynamic theory with practical electrochemical application and then pivots into functional group organic chemistry. In Part A, you study how pressure affects phase transitions, how dilution affects molar conductance versus specific conductance, how to use standard electrode potentials to predict redox spontaneity, and how Gibbs phase rule governs multicomponent systems. Part B brings in amines, carboxylic acid derivatives, carbohydrates, proteins, and Gabriel synthesis. That is why this paper feels broad. It genuinely is.
At Unnati Education, we have helped many IGNOU BSCG and BSCM students prepare for BCHCT-135. We know which numerical questions need the most working and which organic reactions catch students off guard.
BCHCT 135 Exam Pattern and Marks Breakdown (BCHCT-135 December 2025 Question Paper)
The paper is divided into Part A carrying 25 marks and Part B carrying 25 marks. From each part, you attempt any five questions in separate answer sheets. All questions carry equal marks within their respective parts. Total marks are 50. The exam duration is 2 hours. Here is the important part: because both parts are answered in separate answer sheets, you need to manage your time consciously across both sections from the moment you start.
All Questions ā BCHCT 135 Question Paper December 2025 IGNOU (Complete List)
Here is the complete question paper exactly as it appeared in the IGNOU Term-End Examination, December 2025.
Part A (Marks: 25)
- Question 1. (a) Explain whether the melting point of a substance will be lowered or raised by applying pressure if solid does not float on the liquid. (3 marks) (b) Explain why molar conductance of a solution of electrolyte increases on dilution whereas the conductivity (specific conductance) decreases on dilution. (2 marks)
- Question 2. (a) From the data given below, predict whether the following redox reaction would be spontaneous or not: (2 marks) 3Ni(s) + 2Al3+(aq) ā 3Ni2+(aq) + 2Al(s) Given that: EĀ°(Ni2+/Ni) = -0.25 V EĀ°(Al3+/Al) = -1.66 V (b) Briefly explain the following terms in the context of the phase diagram of condensed two-component systems: (3 marks) (i) Isopleth (ii) Tie line (iii) Lever rule
- Question 3. (a) Explain why H+ and OH- ions in aqueous medium have exceptionally high ionic conductances. (3 marks) (b) A conductivity cell with parallel electrodes was used to measure the resistance of solution. The resistance of a solution having specific conductivity equal to 1.5 x 10-2 S cm-1 is found to be 150 ohm. If each electrode has an area 2.0 cm2, find the distance between them. (2 marks)
- Question 4. (a) Draw the temperature-composition diagram of a system exhibiting negative deviation from Raoult's law and explain the distillation of such a mixture. (3 marks) (b) Find the number of components for the following system: (2 marks) NH4Cl(s) = NH3(g) + HCl(g) when: (i) p(NH3) = p(HCl) (ii) p(NH3) is not equal to p(HCl)
- Question 5. The aqueous solution of an acid is provided with a platinum electrode around which hydrogen gas is bubbled at a pressure of 1 bar. The hydrogen electrode so obtained is combined with zinc electrode to construct a galvanic cell. If the e.m.f. of the cell at 298 K is found to be 0.39 V, find the pH of the solution. (Given that: EĀ°(Zn2+/Zn) = -0.77 V.) (5 marks)
- Question 6. (a) State Ostwald's dilution law. (1 mark) (b) At 18Ā°C, the molar conductivities at infinite dilution of NaCl, NH4Cl and NaOH are 108.9, 129.8 and 217.4 S cm2 mol-1, respectively. If the molar conductivity of a 0.01 M solution of NH4OH is 9.33 S cm2 mol-1, calculate its degree of dissociation of NH4OH at this dilution. (2 marks) (c) What are the advantages of potentiometric titrations over conventional volumetric titrations? (2 marks)
- Question 7. (a) Derive Gibbs' phase rule for a non-reactive system of C components having P phases. (3 marks) (b) Differentiate between Galvanic and Electrolytic cells. (2 marks)
Part B (Marks: 25)
- Question 8. Complete the following reactions: (5 marks) (i) CH3-C(=O)-Cl reacting with H2/Pd-BaSO4 in quinoline ā ? (ii) Aniline (with NH2 group) reacting with NaNO2 + HCl at 0Ā°C ā ? (iii) Aniline (with NH2 group) + CHCl3 + 3NaOH ā ? (iv) Phenol (with OH group) + C6H5COCl with NaOH ā ? (v) CHO-(CHOH)4-CH2OH reacting with Br2/H2O ā ?
- Question 9. (a) Briefly explain cleansing action of soap. (2 marks) (b) Write the steps involved in preparation of anilide (N-phenylbenzamide) from aniline. (3 marks)
- Question 10. (a) Arrange the following carboxylic acid derivatives in decreasing order of their reactivity towards nucleophilic acyl substitution, giving reasons: (3 marks) (i) CH3-C(=O)-O-C(=O)-CH3 (ii) CH3-C(=O)-NH2 (iii) CH3-C(=O)-Cl (iv) CH3-C(=O)-OCH3 (b) Which is more basic ā methylamine or aniline? Give reasons. (2 marks)
- Question 11. (a) "Direct nitration of aniline using nitric acid and sulphuric acid results in formation of large amount of meta-nitroaniline, in addition to the para-substituted products." Explain. (2 marks) (b) Why is sucrose known as an invert sugar? (1 mark) (c) How will you synthesize the following from diazonium salt? (2 marks) (i) 4-Bromo-1-methyl benzene (ii) Toluene
- Question 12. (a) What are epimers? (1 mark) (b) Name the linkage present in cellulose. (1 mark) (c) Explain mutarotation taking example of glucose. (3 marks)
- Question 13. Write the steps involved in the preparation of alanine using Gabriel-Phthalimide synthesis. (5 marks)
- Question 14. (a) Differentiate among the primary, secondary and tertiary structure of proteins. (3 marks) (b) Write Haworth structure of maltose. Name the monosaccharides present in it. (2 marks)
BCHCT 135 Syllabus Topics Covered
The syllabus for BCHCT-135 brings together two distinct chemistry disciplines under one exam. Part A covers solutions and phase equilibrium including Raoult's law deviations and phase diagrams, electrochemistry covering electrode potentials and galvanic cells, conductance including Ostwald's dilution law and molar conductance calculations, and thermodynamic tools like Gibbs phase rule. Part B covers functional group organic chemistry including amines, carboxylic acid derivatives, carbohydrates like glucose and maltose, proteins and their structural levels, and Gabriel-Phthalimide synthesis for amino acids.
Sample Answer Preview ā BCHCT-135 Solved Question Paper Explanation
Take Question 5 on pH calculation as a strong example. The approach starts by identifying the cell: zinc electrode paired with a hydrogen electrode. The standard electrode potential for zinc is given as -0.77 V. Since the hydrogen electrode acts as the cathode here, you calculate the cell EMF as EĀ°(cell) = EĀ°(cathode) - EĀ°(anode). Using the Nernst equation and the given EMF of 0.39 V at 298 K, you solve for the hydrogen ion concentration and then convert to pH. That step-by-step working with clear formula application is exactly what the BCHCT-135 solved question paper from Unnati Education delivers.
How to Write High-Scoring Answers in BCHCT 135 Exam
Chemistry papers at this level reward clarity and structure in equal measure. For numerical questions like Question 3(b) and Question 5, always write out the formula first, substitute values with units clearly shown, and present the final answer with correct units. For theory questions, a short definition followed by a logical explanation works best. Diagrams for phase equilibrium questions add real value and are expected. In Part B, organic reaction completions need the correct product drawn or written clearly, not approximated. Most students lose marks not because they do not know the chemistry but because their working is incomplete or unclear.
Who Should Use This BCHCT-135 Solved Question Paper December 2025?
This solved paper is built for IGNOU BSCG and BSCM students appearing for BCHCT-135 in the current or upcoming Term-End cycle. It is equally useful for chemistry students who want to revise electrochemistry, phase equilibrium, and functional group reactions in a structured exam-ready format. Repeat candidates who want to identify where their previous answers fell short will find this especially helpful. If you are preparing independently without a classroom, having model answers to benchmark your own writing against makes a genuine difference.
Why This Is Better Than Free BCHCT-135 December 2025 Question Paper PDFs and Telegram Files
Free Telegram files give you the question paper, full stop. No working for numericals, no mechanism for organic reactions, no explanation of why an answer is structured a certain way. What Unnati Education provides is a complete solved paper where every question has an answer written for IGNOU's specific evaluation pattern. Numerical solutions show full working. Theory answers have definitions, explanation, and relevant examples. Organic reaction answers include the correct product with brief reasoning. That is the actual difference between a question paper and a resource that helps you prepare.
Student Reviews ā BCHCT-135 Solved Question Paper by Unnati Education
"The BCHCT-135 December 2025 paper had a tough numerical on pH calculation and I had no idea how to approach it. The solved paper from Unnati showed the full working step by step. That one question alone was worth it." ā Priya N., BSCG student, Lucknow
"Part B organic reactions always confused me. Especially the Gabriel synthesis and protein structure questions. The solved paper explained both clearly enough that I could write them in my own words in the exam." ā Sameer D., BSCM student, Pune
"Much better than free PDFs. Those only gave me the questions. Unnati gave me the answers, the working, and the reasoning. Completely different level of help." ā Komal S., IGNOU student, Jaipur
How to Get the BCHCT-135 Solved Question Paper December 2025 ā Step by Step
- Contact Unnati Education via WhatsApp or the link on this page.
- Share your programme name, confirm your course code as BCHCT-135, and mention the December 2025 exam cycle.
- We confirm availability and send your solved paper digitally, usually within a few hours of your message.
Frequently Asked Questions
What is BCHCT-135 in IGNOU?
BCHCT-135 is a chemistry paper offered under the IGNOU Bachelor of Science General (BSCG) and Bachelor of Science Multidisciplinary (BSCM) programmes. It covers Solutions, Phase Equilibrium, Conductance, Electrochemistry and Functional Group Organic Chemistry-II. The paper is divided into Part A covering physical chemistry and Part B covering organic chemistry, each carrying 25 marks for a total of 50 marks.
What is the exam pattern for BCHCT-135 December 2025?
The BCHCT-135 December 2025 paper carries a total of 50 marks and runs for 2 hours. It is divided into Part A and Part B, each worth 25 marks. Students must attempt any five questions from Part A and any five questions from Part B, answered in separate answer sheets. All questions within each part carry equal marks, making question selection an important strategy for maximising your score.
Which chemistry topics are most important for BCHCT-135?
Based on the December 2025 paper, the most important topics in Part A are electrochemistry including EMF calculations and electrode potentials, conductance including molar conductance and Ostwald's dilution law, phase equilibrium including Raoult's law deviations and Gibbs phase rule, and numerical problems. In Part B, key topics include organic reaction completion, amine chemistry, carbohydrate structures including mutarotation and Haworth structures, protein structure levels, and Gabriel-Phthalimide synthesis.
How can I download the IGNOU BCHCT-135 question paper?
The BCHCT-135 December 2025 question paper is available right here on this page in full. You can also find official question papers on the IGNOU website under the Term-End Examination section. For the solved version with complete worked answers, contact Unnati Education directly via WhatsApp or the contact link on this page and we will send your solved paper digitally within a few hours.
About Unnati Education ā IGNOU Study Material Experts
Unnati Education has been supporting IGNOU students across India for several years. Our team includes science graduates with specialization in physical chemistry and organic chemistry, along with deep experience in IGNOU examination patterns across BSCG, BSCM, and other science programmes. Every solved paper we prepare is written for IGNOU's specific evaluation style, with full working for numericals, clear theory answers, and accurate organic chemistry responses. Students return to us across exam cycles because the material genuinely reflects what the exam expects.
Explore More IGNOU BCHCT-135 Solved Papers and Study Material
You might also find these resources useful: previous year solved question papers for BCHCT-135, assignment solutions for BCHCT-135 for the current session, chapter-wise chemistry notes for Solutions, Phase Equilibrium, Conductance, and Electrochemistry, topic-based guess papers drawn from repeating exam patterns, and solved papers for other BSCG and BSCM chemistry course codes.
Get Your BCHCT 135 Question Paper December 2025 Solved Paper Now
You have read through every question in both parts of the paper. You know exactly what December 2025 asked. Now what you need are solved answers with full working, clear theory, and organic chemistry responses written specifically for IGNOU's evaluation. Contact Unnati Education today, get your BCHCT-135 solved question paper December 2025, and walk into your preparation with real direction and real confidence.